An unlikely coalition of scientists, business leaders, and politicians is trying to launch one of the most complicated construction projects in U.S. history. They want to unleash the Mississippi River, to undo the damage that the government has caused by spending the last century taming it. They say that's the only way to stop the vast wetlands that form Louisiana's coast from vanishing. Every year, a chunk of Louisiana's coast the size of Manhattan crumbles and sinks into the sea. Studies suggest that if the trend continues, major industries could be disrupted, from oil-and-gas, to seafood, to shipping. But scientists acknowledge that as they try to repair nature, they might trigger a new round of side effects.

You'd think that a fisherman like George Barisich would be thrilled that officials want to save the wetlands in Louisiana. But he says wait until you hear his story. As he begins to tell it, the setting sun is turning the sky pink, he's dropping his shrimp netslike giant spider websinto a bay on Louisiana's coast. And Barisich says, he's living proof that when the government tries to solve one problem, they just create another.

Barisich looks like Groucho Marx in blue jeans. He says, don't get him wrong, he knows that the shrimp and crabs and redfish down here spend a lot of their lives in the wetlands, so if the wetlands keep crumbling, fishermen could be doomed. But, he says, he's been catching shrimp in this bay since he was a kid. He worked on this white and orange boat with his father. And over the years, Barisich learned where the shrimp like to feed and he learned the best cycles of the moon. He was sort of like an angler who outwits his trout. Then a few years ago, the shrimp stopped showing up.

"They never came in, they never came in," explains Barisich. "So you lost the production from that particular area, and you just had to get up and leave."

The Corps Rebuilds

Every fisherman knows that some years are better than others. But Barisich says he knew instantly what was wrong: It was the government. The U.S. Army Corps of Engineers had just built a pilot project to try to rebuild the wetlands.

"They made a change without exploring all the potential hazards of doing something of this nature," describes Barisich. "Now, I know for a fact that nothing has ever been done on this scale before. That's what bothers us. They're gonna hurt me and it's just like nobody cares."

They call the pilot project Caernarvon. It's a long concrete structure that sits on the banks of the Mississippi, and at first, it doesn't look like something that can help transform the region and cause a legal uproar. It looks like a small dam.

Jack Fredine supervises the project for the U.S. Army Corps of Engineers. The official name is the Caernarvon Water Diversion Project.

"We're downstream of New Orleansabout 20 miles," Fredine says. "We have a structure that's built here into the levee of the Mississippi River, which is here for flood control. It's like five square holes going underneath the river from 500 feet and each hole is 15 feet square."

Scientists say that the vast wetlands in Louisiana are vanishing partly because the U.S. Army tamed this river too much. The Army built two thousand miles of levees all along the Mississippi, so the river would stop flooding. But studies over the last few decades show that these wetlands need to be flooded. They need regular doses of river-water and mud to thrivethe levees are starving them to death. So the government has launched the Caernarvon project to see if it can revive the wetlandswithout flooding people's homes. When Fredine gives the word, a workman presses some buttons.

And suddenly, the placid surface of the Mississippi River begins bubbling and roiling. Huge gates are opening under water, and uncovering the giant holes, and the river is pouring through the levee into a marsh on the other side.

"The original concept of this was to mimic the spring floods," explains Fredine, "to replenish the marshes with freshwater that would have been coming through if the levees weren't here in the way to block out the floods."

So, in a way, technology hurt nature in the first place, and now they're using nature to repair nature, to mimic it.